To what extent do variations in the care delivered at acute and post-acute care facilities contribute to current patterns of long-term survival and functional recovery for older adults with acute medical and surgical conditions? This question, which is fundamental to understanding the relationship between medical care and outcomes for older adults, carries profound policy implications. Proposed delivery-system reforms, such as accountable care organizations and bundled payments, focus on the end results of treatment, rather than the quantity of services provided in any given setting, as the proper basis for determining health care payments. As a result, knowing the extent to which discrete components of the health care system now contribute to variations in patient outcomes is vital to the effective design, implementation and evaluation of these policy strategies. My project will add to current knowledge as to how variations in the care delivered within two distinct components of the U.S. health care system-acute and post-acute care facilities-each contribute to observed patterns of outcomes among older adults with acute illnesses. To do so, it will focus on the care and outcomes of older adults with hip fracture, a highly morbid condition that affects over 300,000 older U.S. adults each year. Taking a mixed-methods approach, it will incorporate a national retrospective cohort study of hip fracture patients and a series of qualitative interviews with health care providers and administrators to: 1) measure the association of specific acute and post-acute care facility factors with 6-month survival and functional recovery after hip fracture~ 2) compare the relative influence of acute versus post-acute care facility factors on 6-month survival and functional recovery after hip fracture~ and 3) characterize qualitative differences in institutional approaches to hip fracture care across a range of acute and post-acute care facilities. Through this course of research, my project will offer new insights into the extent and causes of variations in hip fracture outcomes and serve as a model for understanding the systemic determinants of health outcomes across a broad range of medical and surgical conditions affecting older adults. Along with a structured course of mentoring and research training, this project will provide me with the skills and experiences needed to reach my career goal of becoming a leading researcher in aging dedicated to improving systems of care and outcomes for older adults undergoing hospitalization and surgery in the U.S.